Lubricating mixture for cold reducing mills



Patented Nov. 24, 1942 um'rao STATES PATENT OFFICE atta n LUBRIOA'HNGmxrun aanuom a m: com G mus A m1 1). 8mm, Gary, Ind.

No Drawing.

Application August 15, 1939, Serial No. 290,312 1 cam 01. 80-60) Thepresent invention relates in general to improvements in the art of coldreducing metals such as exemplified in the patent granted to Edwin T.Lorig, Patent No. 1,973,684, issued September 11,-193'4', In the saidLorig patent, there disclosed a process for cold reducing metal,

especially in rolling thin,.wide strips of steel on as4-high mill, thepatent disclosing the broad pointed out in detail in the followingspecification and in the subioined claims.

In accordance with the present invention. in-

water and engine oil, I utilize; as a combined lubricant and coolant, a.mixture of. palm oil and water which is preferably emulsified so thatthe mixture does not break down during the roll-' ing operation. Thepresent invention overcomes problems due to the entry mineral oil intolubricant and coolant, this mineral oil coming from leakage of the milllubricating system and also being carried by the material being rolled,which material is frequently coated with mineral oil for the preventionof rust or corrosion,

In practice it was found that the addition of mineral oil wasdetrimental as it did not readily jenter into suspension with otheroils, thusthe mixture became unduly thick, clogging the filter screensand other parts of the spraying'systeml In my research, to overcome thediflieulties inherent in the use of solutions employing mineral oil,engine oil and the like, I discovered that by utilizing a mixture ofpalm oil and water totallyunexpected'and surprising results were securedwithout the disadvantage ofclogsing thecirculating system; even when thepahn oil and water In practice the solution or liquid mixture is sprayedthrough nozzles against the surface of the working rolls and on thesurface of the strip being rolled, pressure being applied by centrifugalor other pumps driven by variable speed motors. The solution, as itdripsfrom the rolls and the work, is collected in a sump wherein thetemperature is controlled vas desired by a suitable heat exchanger, thesolution or mixture bestead of applying water alone, or a mixture of ingpumped from the sump into the circulating system, sprayed on the'rollsand surface of the strip being reduced, and the excess mixture beingreturned again to the sump. Practice has shown that under my invention,by utilizing a solution of palm oil and water, the following advantagesaccrue: The cost of the solution is reduced by approximately 95%; theindividual mill loads are appreciably lowered; a definite roll contourcan be maintained; the mill can be operated under a uniform screwpressure, regardless of I the degree of hardness of the metal beingreduced, by controlling the oil content of the rolling solution; a moredesirable strip shape is obtained due to the fact that the reducingmembers are cooled and lubricated as desired; materialre- [duced in theimproved solution is more easily cleaned preparatory to annealing; dueto the uniform pressures exerted on the working members, it ispossible-to maintain a materially better surface condition of theworking rolls, thus prolonging their life; the material is moreaccurately rolled to the desired ga e; strip breakage such as heretoforecaused by non-uniformity of mixture became somewhat contaminated withthe lubricating oil or other mineral oil.

I have determined that for most efllcient resuits, the combinedlubricant and coolant should 125 degreesl 'ahrenheit.

:contain from 1 to 40 per centpalmoil and from 60 to 99 pe'r cent water.

mixture does not attain a temperature below '40 degrees orabove 212degreesFahrenheiuI find that for most efiective results, it is desirableto Whileanymixture within this range will give good results when theemploy a' mixture comprising approximately-.15 4

per cent palm oil with the remaining per cent water. ,The optimumtemperature is approxi- 1 solution is practically eliminated, and theenter- :ing of the strip into the mill is expedited because reductionthereof at the point of entry is more nearly uniform.

In practice, the ingredients of the solution may be emulsified by theuse of, eithera mechanical homogenizer or a chemical emulsifien' Theemulsification can be obtained by mechanical agitation-elther in thenature of a separate agitating step, or the constant interaction of therolls of the mill with the workcan be utilized for homogenization of theingredients of the mixture.

Having thus described the invention and the advantageous features whichdistinguish it from the prior art, what I claim is:

1. The method. of cold reducing metals which consists in lubricating andcontrolling the tem-- .-perature of the reducing members by applying tothe exterior working surface thereof a liquid mixture consisting solelyof a homogenizedemulsion of palm oil and water.

66 2. The method of cold reducing metals which consists in lubricatingand controlling the temperature of the reducing members by applying tothe exteriorworking surface thereof a liquid mixture consisting solelyof a mixture of from 1 to 40 per cent palm oil and the balance water tomake 100 per cent.

3. The method of claim 2 further characterized in that the liquid isapplied at a temperature of approximately 125 degrees Fahrenheit.

4. A solution for controlling the temperature of reducing members of acold metal reduction apparatus' and for lubricating the metal beingreduced, consisting solely of a mixture of from 1 to 10 to make 100 percent.

EARL D. SPANGLER.

